We'll return now to the story of one young woman and her two new hands. A double transplant. But even with those, she now faces a new battery of difficult challenges. Once again, here's abc's john donovan. Reporter: After nearly 12 hours in the operating room, something quite rare. Transplanting two donor hands on to 28-year-old lindsay. So have you looked yet? No. Okay. I've only looked -- peeked down at this one thumb. Reporter: Inside this cocoon is a new lindsay, hesitant to see what's happened to her overnight. What's finally happened. They feel like normal fingers, normal hands. Reporter: The initial signs good. This is more than we could ever hope for. Your blood pressure is good. All the parameters are good resulted to how the blood flow is in and out of her new arms. This is -- if you will, a picture perfect so far. Reporter: You haver Reporter: Less than a month after surgery, lindsay is out of icu and well into therapy. It gets easier, are you helping me? No, you're doing that. Each repetition should get easier because you're getting looser. How many is this? This is only number two. Reporter: She is starting to get to know her new hands. Tell me about the first time you saw them, that they were yours. The first couple of days, i refused to look at them. Reporter: How come? It was kind of like one of those carry movie kind of moments. You know, that's all it was. It was one of those I'm too scared to look because it's reality. Reporter: But it's not yet a perfect reality. To prevent rejection, the surgeons had to leave pouchs of excessive fat and skin on her normally toned and thin arms. Her new hands and arms look like they belonged to someone else. Reporter: And the skin color is never going to be the same, the lower arms to your upper arms. That will always be that way? It's hard for me to answer questions like that because I'm just so grateful to have them, for them to not match is sort of, to me -- Reporter: Beside the point? Yeah. Start with your left wrist. Reporter: January 2012, four months after surgery, her doctors are amazed by the pace of her recovery. They didn't expect fine motion control for at least another 12 to 18 months. But -- to see this at this early stage is very encouraging. Reporter: Her muscles are reacting and she can pick up lightweight objects. Let go. This is the time, where hours each day it's your job. All right, there she goes. Reporter: Finally, going home on a cold day last february, five months after that urgent call to come in for the surgery. The prognosis, for both hands couldn't be better. Oh, my god, look at your extension. That's incredible. Hold them out, squeeze. Reporter: June, 2012, nine months after the surgery, she can extend and move her wrists and fingers and sense hot and cold, a tingling sensation that bothers her. Nevertheless, indicates that nerves are growing back. Her function continues to improve dramatically. At a very accelerated rate in terms of her nerve regeneration. It's giving her more strength. Reporter: But you can see the weight gain. 40 pounds. The result of extra steroids required when her body threatened to reject the transplant. That crisis receded, but the weight gain is something lindsay finds more deeply discouraging than she expected. I hear you on the steroids. We want you off these steroids as fast as we can get you off them. But to compromise and risk rejection, that's the thing that

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